Electric-fuse case.



. T. E. MURRAY.

ELECTRIC FUSE CASE. APPLICATION FILED SEPT.V28,1908.

Patented July 27,1909.

ELE G TRIC-FUSE CASE Specification of Letters Patent.

Patented July 2'7, 1909.

Application filed September 23, 1908. Serial No. 455,081.

T all whom it may concern:

Be it known that l, Tnorms E. MURRAY, a

- citizen of the. United States, residing at New York, in the county ofNew York and State of New York, have invented a certain new and usefulImprovement in Electric-F use Cases, ofwhich the following is aspecification.

The invention relates to electric fuse cases or plugs, and consists inthe construction of the case, and in the-means for diffusing the shockdue to the blowing of the fuse. and so protecting the material of thecase from breakage.

In the. accompanying lra\\-'ings---Figure 1 is a perspective view on anenlarged scale, of one of the metal caps to which the end of the fuse isattached. Fig. 2 is a vertical longitudinal section of my fuse case onthe line ."r, a, of Fig. 3. Fig. 3 is a cross section on the line 3 y,of Fig. 2. Fig. 4 shows the fuse se aratcly. Fig. 5 is an end elevationof my fuse case.

Similar numbers of reference indicate like parts.

The fuse case proper, 1, is preferably made of porcelain and in archedshape, as shown, With two integral projections v2, 2), on its lowerside, which enter the usual block or holder, not shown, containing thecircuit connections. On each of said projections is a sheet metal cap 6,having bent up side walls 7, whic i, when the cap is in place, cover twosides of the projection. Between the walls 7 on the outer side of thecap is a bent up portion 8, having two clips 9, 10, and a middle lug llhaving outwardly projecting edges 12, also forming a clip. On the innerside of the cap is a bent up portion 12}, having two clips 14, 15.. The.cap is secured on the projection by bending over the. clips 9, 10, intoa transverse recess 16 on the outer side of the. projection, and bybending over the clips 14, 15 into a. similar recess 17 on the innerside of said projection.

The fuse 4, shown separately in Fig. 5, has

a contracted portion at 5. It is received in an arched bore in the fusecase, the ends of which are closed by plugs 18 of cement. Theextremities of the fuse pass through the cementplugsand are held in theclip formed by the lug 1], the projecting edges 12 thereof being foldedover upon the. fuse, as shown in Fig. 5. ing the fuse is filled with aninert and refractory pulverized material, such as pulverized magnesia,or the like.

I have foundthat While the disrupting effect ofthe fuse explosion, uponan inclosing of fictile material of given thickness,

may be prevented by embedding the fuse in aninert and refractory body,which absorbs the shock and so protects the said material from breakage,it is possible to secure such protection with a thinner case by Wrappingthe fuse with a non-combustible fabric, such as asbestos paper. Thiswrapping, indicated at 19, prevents concentration of the explosive shockand diffuses it over an area in some. degree dependent upon the lengthof the applied layer.'

I claim:

1.. The combination of a fuse case of fictile material, a fusetl'ierein, a Wrapping of noncombustible fabric surrounding said fuse,and a body of inert and refractory pulverized material completelyfilling said case and stir-- rounding said fuse and wra iping.

2. The combination of a fuse case of "fie-tile material, a fuse therein,a wrapping of noncombustible material surrounding said fuse mer aportion of the length. tl'iereof, and a body of inert and refractorypulverized ma tcrial completely filling said case and sur rounding saidfuse and wrapping.

- in testimony whereof I have affixed my signature in presence of twoWitnesses.

Tl'lOll'fAS- E. MURRAY.

Witn esses:

GERTRUDE T. Poirrnn, MAY '1. McGAmir.

The space Within the case surround

